Doc comments not included on #[memoize]-annotated function

[ageofabenius]

When annotating a function with #[memoize], doc comments on the annotated function are not discoverable by rust-analyzer.

In the cargo doc-generated documentation, the following functions are described for a test_function function:

1. test_function
2. memoized_flush_test_function
3. memoized_original_test_function    <- doc comments appear here
4. memoized_size_test_function

Ideally, the doc comments would appear on 1. test_function itself. This would make them available to rust-analyzer and other tools.